Report: Microburst caused C-130 crash

Nov. 14, 2012 - 06:14PM
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Last Updated: Nov. 14, 2012 - 06:14PM |

A Modular Airborne Fire Fighting System-equipped C-130 Hercules similar to this one crashed in July while battling wildfires in South Dakota. Four aircrew from the North Carolina Air National Guard died in the crash. (Air Force)

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A C-130 fighting fires in South Dakota crashed in July after it flew through a small and intense thunderstorm known as a "microburst," an investigation into the crash determined.

Four members of the North Carolina Air National Guard's 145th Airlift Wing were killed in the crash: Lt. Col. Paul K. Mikeal, Maj. Ryan S. David, Maj. Joseph M. McCormick and Senior Master Sgt. Robert S. Cannon.Two other airmen were injured in the incident.

Even though the crew had been told to drop its retardant on the fire, they should have decided not to do so because of weather conditions and other indications that the situation was too dangerous, said Brig. Gen. Randall Guthrie, who led the investigation into the crash.

"If you add all of the pieces up, it was very clear that they shouldn't have attempted the second drop, that with all of the different meteorological conditions, all of the different operational conditions that were going on there, they should not have gone ahead with that second drop," Guthrie told reporters during a conference call on Wednesday.

On its previous run, the plane was forced to push its engines to maximum power, yet the plane was unable accelerate, Guthrie said.

"Then, after that, as they came around for the second drop, they noticed multiple different indicators of what was going on weather-wise, all of which have an impact on the capability of what the aircraft can do," he said.

The plane leading the C-130 into the second run ran into the same microburst and came within 10 feet of the ground, but it and another aircraft involved did not effectively communicate to the C-130 crew how severe the turbulence was, Guthrie said.

"As to why both of them didn't show a greater sense of urgency and be clearer, they also commented that they didn't really add all of the pieces up themselves," he said.

Another contributing factor was the crew had conflicting guidance on how close they could get to thunderstorms, he said. Air Mobility Command said they could get up to 5 nautical miles to storms, but the National Guard Bureau told them that they needed to stay 25 nautical miles from thunderstorms.

"Based off our interviews with all of the other crewmembers that fly this type of mission, there was confusion as to which set of guidance was appropriate in this particular situation," Guthrie said. "All of the indications we had was the crew believed the 5 nautical miles was what the correct number was."

Once the C-130 flew into the microburst, it went into a descent that was "unrecoverable," he said. The crew tried dumping the retardant, but the plane kept falling. In the final seconds, they managed to position the plane in a way that allowed the two crewmembers in the rear would survive.

Although the lead plane had asked the C-130 to do the second run, the crew still could have called it off.

"Our analysis was that there was more indications than just the weather that they had that indicated what was going on," Guthrie said. "They were not ordered to do it. Anybody could have said, ‘No, we're not going to do it,' and they wouldn't have done it. They always have that."

Before the crash, a pilot with the Wyoming National Guard's 187th Airlift Squadron told Air Force Times that high winds, thick smoke and mountainous terrain were making firefighting efforts difficult

The high winds, thick smoke and mountainous terrain makes firefighting efforts even more challenging, said Maj. Neil Harlow, a pilot with the Wyoming National Guard's 187th Airlift Squadron.

Crews had been forced to drop fire retardant at 10,000 feet, much higher than the normal drops, which are usually made at 8,000 feet, said Maj. Neil Harlow.

"The conditions couldn't be worse for aircraft," Harlow said. "We have high-pressure altitudes in excess of 10,000 feet just for takeoffs. We're fully loaded with slurry and fuel. It makes it extremely difficult to get the plane to perform for you."